高硒氰化银泥回收硒的研究与应用

Research and Application of Recovering Selenium from Silver Cyanide Mud with High Selenium

高硒氰化银泥具有硒、锌、铜含量高的特点。为了给后续金银提取创造有利条件,本文研究了控电氯化全湿法预处理技术,重点分析了硫酸、氯化钠用量对氯化反应电位的影响,探究了碱溶硒时碱浓度、温度、时间对硒回收率及品位的影响。试验结果表明,当液固比为3∶1,氰化银泥∶氯化钠∶硫酸=5∶1∶3(质量比)时,可加入NaClO_(3)溶液,控制氯化反应电位在750 mV。碱溶硒的最佳条件为:液固比3∶1,碱浓度200 g/L,温度85 ℃,时间3 h。试生产验证了工艺条件,各项技术指标符合预期,经济、环境、社会效益显著。

Silver cyanide mud with high selenium has the characteristics of high content of selenium,zinc and copper.In order to create favorable conditions for the subsequent extraction of gold and silver,this paper studies the full wet pretreatment technology of controlled electrochlorination,and focuses on analyzing the effect of sulfuric acid and sodium chloride dosage on the chlorination reaction potential,and explores the effects of alkali concentration,temperature and time on the recovery rate and grade of selenium when selenium is dissolved in alkali.The test results show that when the liquidsolid ratio is 3:1,and the silver cyanide mud:sodium chloride:sulfuric acid=5:1:3(mass ratio),NaClO_(3) solution can be added to control the chlorination reaction potential at 750 mV.The optimal conditions for alkali-dissolving selenium are as follows:liquid-solid ratio 3-1,alkali concentration 200 g/L,temperature 85℃,time 3 h.Trial production has verified the process conditions,all technical indicators are in line with expectations,and the economic,environmental and social benefits are remarkable.